import random
a='abcdefghijklmnopqrstuvwxyz'
d={}
lst=[]
for n in range(100):
    b=random.sample(a,k=2)
    c=b[0]+b[1]
    if c in d.keys():
        d[c]+=1
    else:
        d[c]=1

print(sorted([(i[1],i[0]) for i in d.items()],reverse=True))


# 完成的不错
